Tang Yulu, Zhong Bifeng, Qu Bing, Feng Shujin, Ding Sanglan, Su Shijun, Li Zhi, Gan Zhiwei
College of Architecture and Environment, Sichuan University, Chengdu 610065, China.
Environ Sci Process Impacts. 2017 May 24;19(5):752-757. doi: 10.1039/c7em00114b.
A total of 28 groundwater, paired farmland soil, lettuce, and its rhizosphere soil samples were collected from Chengdu, China to detect perchlorate levels and to evaluate the relationships of perchlorate concentrations among these matrices. The perchlorate concentrations in the groundwater, farmland soil, lettuce, and rhizosphere soil samples ranged from below detection limit to 60.2 μg L, from below detection limit to 249 μg kg dry weight (dw), from 2.07 to 1010 μg kg wet weight, and from below detection limit to 314 μg kg dw, respectively. Significant correlation was found in the perchlorate levels among the farmland soil, lettuce, and rhizosphere soil, suggesting that they have common pollution sources, or perchlorate might transfer from farmland soil-rhizosphere soil-plant. However, there is no significant correlation between groundwater and the other three matrices, indicating that infiltration from perchlorate contaminated farmland soil was not the predominant source for groundwater pollution in Chengdu. The perchlorate concentrations in the farmland soil and lettuce samples were significantly higher than those in the rhizosphere soil, primarily due to uptake of perchlorate through the rhizosphere micro-environment by lettuce, or accelerated degradation by rhizospheric microorganisms, which contributed more needs further investigation.
从中国成都共采集了28份地下水、成对的农田土壤、生菜及其根际土壤样本，以检测高氯酸盐水平并评估这些基质中高氯酸盐浓度之间的关系。地下水、农田土壤、生菜和根际土壤样本中的高氯酸盐浓度分别在检测限以下至60.2 μg/L、检测限以下至249 μg/kg干重（dw）、2.07至1010 μg/kg湿重以及检测限以下至314 μg/kg dw之间。在农田土壤、生菜和根际土壤的高氯酸盐水平之间发现了显著相关性，这表明它们有共同的污染源，或者高氯酸盐可能从农田土壤-根际土壤-植物转移。然而，地下水与其他三种基质之间没有显著相关性，这表明高氯酸盐污染的农田土壤的渗入不是成都地下水污染的主要来源。农田土壤和生菜样本中的高氯酸盐浓度显著高于根际土壤中的浓度，这主要是由于生菜通过根际微环境吸收高氯酸盐，或者根际微生物加速降解，这其中哪种因素贡献更大还需要进一步研究。
